Oh, FS... I am thinking of you and so, so, so feeling for you. I can imagine exactly the situation (again because I feel our Hs are so similar in so many ways).
I hope you aren't feeling badly about hanging up on him. He deserved it. Both times, and you are under no obligation to take abuse from him. In the mediation case you are 110% in the right-- wtf is he thinking that there would be a 50/50 childcare arrangement but he could actually end up doing whatever he pleased? Unbelievable. And he's clearly just feeling guilty and bad about the other mums thinking he's a jerk (I would bet other things beyond this one incident are leaking into him feeling like this, like the fact that he left you and what he imagines the other moms think about that, plus the bunny boiler at school) and wanted to take it out on you. Good for you for not letting him do that. And if you let off some steam in the meantime.... oh well. We can't all be saints every day.
I so badly want for you a mental break and be able to spend a little time not in a funk. Is there anything you can do? take an afternoon off of work and pick them up early from school and do something silly and fun?
On the fear and letting go... I think if you can make that happen, release your fear and just let go and let what comes come... I feel that doesn't necessarily mean you're letting hope go for R with your H. it just means you're going to be okay no matter what happens. Which you know you are.
Finally, just wanted to tell you that you were a huge inspiration to me... I dropped off an entire car load of giveaway today and threw out six giant bags of kid trash. It feels AMAZING. Thank you.
(((FlySolo))) we are here for you!
Me (46) H (42) M:14 T:18, D9 & D11 4/19 - 12/19: series of escalating BDs 9/20 - present: R and piecing